By Nicole A. Elliott
Sentinel staff writer

RECALCULATED ZONERS — Kevin Magnanti, garden center manager at Ace Hardware, shows off a purpleteal sandberry. Magnanti said Rome has moved from Zone 4 to Zone 5 meaning the growing season has changed for some plants. (Sentinel photo by John Clifford)

Will Oneida County gardeners now be able to plant Florida palm trees in their back yards?

Not exactly, but according to the U.S. Department of Agriculture, new factors applied to refined formulas call for a change in the area’s planting zone.

The USDA released a new version of its Plant Hardiness Zone Map this month, which helps gardeners and growers decide what type of plants and seeds to sow. The map is based on the average annual minimum winter temperature, divided into 10-degree Fahrenheit zones.

Much of central New York used to lie in zone 5a, with the lowest average temperature reaching between -20 and -15. Now most of the area, including central Oneida County, lies within 5b, meaning that average low temperatures have risen an average 5 degrees — to between -15 to -10.

The majority of Oneida County, however, remains in zone 5a, while most areas north lie in zone 4b, with average low temperatures of between -25 to -20. The northeastern tip of Oneida County lies in zone 4a, with the lowest average temperatures reaching between -30 to -25.

According to the USDA website, the new zone map uses information not available in 1990, the last time hardiness zones had been updated, including algorithms that take into account elevation changes and nearness to large bodies of water and terrain. It also uses weather data collected from 1976 to 2005.

Holly Wise, educator at Cornell Cooperative Extension of Oneida County, said the change in planting zones won’t make much of a difference for Oneida County farmers. She said Oneida County already has an array of "micro climates" that allows some vegetation to prosper in some areas, while withering in others just a few miles away.

"In Oneida and Rome, you have a lot of people growing Rhododendron (azaleas) beautifully around their house," where in other areas in the county they are unable to thrive, Wise said. "Rome has a little climate of its own too, and sometimes the snow cover seems to last longer than even here in Oriskany. Oneida is closer to the (Oneida) lake, so they can grow some things better there too. If we were closer to the Great Lakes, that would protect us more from the really cold temperatures, which is why grapes thrive near Lake Erie. But today there are also new varieties of plants that can take the colder temperatures too that people can grow here around their homes."

Information about the shifts in planting zones and the new Plant Hardiness Zone Map can be found on the USDA website: www.planthardiness.ars.usda.gov.